The Photographic Arts Gallery (1149 28th St.)...

The Photographic Arts Gallery (1149 28th St.) is exhibiting new collaborative efforts by Richard Peterson and Sydney Kovac, who as a pair have been making and showing mixed-media works for four years.

Although Kovac specializes in paintings, collages and assemblages and Peterson in photography (he owns the Pink and Pearl Gallery), each one participates so fully in the creative process that their individual contributions have become inseparable.

The components of each work are a black-and-white photographic image (most often of a nude woman), a mat (usually covered in old-fashioned, flowered upholstery fabric) and a vintage carved frame.

Sounds like nothing special, but it looks like something magical.

The secret is close integration. The artists assemble the images, mats and frames compositionally and tonally to create fully integrated works of art.

One of the most successful among the works in the show, all untitled although they are as a group called “Possession,” is No. 3, which consists of a gloriously ambiguous photograph of flowers and assorted vases (toned the palest of pinks), an elaborately flowered mat (with much beige) and an admirably hideous carved gold frame.

No. 4 combines a photograph of a seated nude woman (viewed from above) with a whip, a mat with the partial images of a rattlesnake and a serpentine plant and an appropriate frame. No. 11 combines an image of a Medusa-like plant (which has a human eye) and a mat with repeated images of the top half of the Mona Lisa’s face, covered by collaged butterflies inside a deeply carved frame. This work seems to wondrously expand and contract.

The exhibit continues through March 5.

For the second in its series of “Alcove” exhibits, the La Jolla Museum of Contemporary Art (700 Prospect St.) is featuring the work of Boston-based fiber artist Blair Tate.

Tate, who has exhibited throughout the United States, takes her inspiration from traditional fabrics, such as African weavings, which she translates into a contemporary idiom.

Each of the three works on view is composed of four-inch-wide vertical panels of woven cotton and linen in shades of black and white. Two of the hangings, which combine architectural elegance with the appearance of computer printouts, look like works that sprung from the head.

The least-contrived hanging, “Kente 1,” which reads as a kind of esoteric language or music notation, looks like a work from the heart.

The exhibit continues through April 5.

In its Meyer Gallery, the museum is featuring a recent acquisition, “The Reason for the Neutron Bomb,” by internationally admired artist Chris Burden, of Los Angeles.

The title appears diagonally (lower left to upper right) on the far wall of the gallery, in black block letters. On the floor are rows of nickels combined with the sulfured halves of matchsticks.

A text at the door reads:

“Behind the Iron Curtain, along the border between Western and Eastern Europe, the Soviet Union maintains an army of 50,000 highly sophisticated tanks. The United States possesses only 10,000, and the combined tank strength of all Western European nations, including the NATO forces, is estimated to be no more than 20,000. The Western European forces are outnumbered by more than two to one. This numerical imbalance is the reason given for the existence of the neutron bomb. Each nickel-and-matchstick combination here represents one Russian tank.”

The work is conceptually minimal and visually insubstantial. Without the text, the visual experience would lack meaning.

Burden has created works of art of great significance but this one trivializes art and life.

It remains on view through May 31.